xref: /openbsd/sys/arch/powerpc/include/tcb.h (revision 264ca280)
1 /*	$OpenBSD: tcb.h,v 1.4 2016/05/07 19:05:21 guenther Exp $	*/
2 
3 /*
4  * Copyright (c) 2011 Philip Guenther <guenther@openbsd.org>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 #ifndef _MACHINE_TCB_H_
20 #define _MACHINE_TCB_H_
21 
22 #ifdef _KERNEL
23 
24 #define TCB_GET(p)		\
25 	((void *)trapframe(p)->fixreg[2])
26 #define TCB_SET(p, addr)	\
27 	(trapframe(p)->fixreg[2] = (__register_t)(addr))
28 
29 #else /* _KERNEL */
30 
31 /* ELF TLS ABI calls for small TCB, with static TLS data after it */
32 #define TLS_VARIANT	1
33 
34 /* powerpc offsets the TCB pointer 0x7000 bytes after the data */
35 #define TCB_OFFSET	0x7000
36 
37 #if 0	/* XXX perhaps use the gcc global register extension? */
38 struct thread_control_block;
39 __register__ struct thread_control_block *__tcb __asm__ ("%r2");
40 #define TCB_GET()		(__tcb)
41 #define TCB_GET_MEMBER(member)	((void *)(__tcb->member))
42 #define TCB_SET(tcb)		((__tcb) = (tcb))
43 
44 #else
45 
46 #include <stddef.h>		/* for offsetof */
47 
48 /* Get a pointer to the TCB itself */
49 static inline void *
50 __powerpc_get_tcb(void)
51 {
52 	void *val;
53 	__asm__ ("mr %0, %%r2" : "=r" (val));
54 	return val;
55 }
56 #define TCB_GET()	__powerpc_get_tcb()
57 
58 /* Get the value of a specific member in the TCB */
59 static inline void *
60 __powerpc_read_tcb(int offset)
61 {
62 	void *val;
63 	__asm__ ("lwzx %0, %%r2, %1" : "=r" (val) : "r" (offset));
64 	return val;
65 }
66 #define TCB_GET_MEMBER(member) \
67 	__powerpc_read_tcb(offsetof(struct thread_control_block, member))
68 
69 #define TCB_SET(tcb)	__asm volatile("mr %%r2, %0" : : "r" (tcb))
70 
71 #endif /* 0 */
72 
73 #endif /* _KERNEL */
74 
75 #endif /* _MACHINE_TCB_H_ */
76